also, I don’t think we can play games with making policies which protect people from going off, with the idea that they might come back; every minute, every sin done by a jew is a horrific event – if we can prevent it, we must. or at least we must not remove things which keep people from doing horrible aveiros, even if they might come back in the future; the sum total isn’t where one ends up – every mitzvah and every sin have a cheshbon, and we have responsibility to other jews to protect them from harm.
chazal did away with shofar and 4 minim, mitzvos which save the world, because maybe, one jew might be mechalel shabbos. they didn’t say, “well, it’s just one chilul shabbos, and im sure he’ll keep next week better”